Question

What is the slope of a line perpendicular to the line whose equation is y = − 2/7 x − 5?
A. -2/7
B. -7/2
C. 2/7
D. 7/2

Answer 1

The slopes of perpendicular lines are negative reciprocals. That means that when you multiply the slopes of two perpendicular lines, you get -1.
y = -(2/7)x - 5 is in slope intercept form which is y = mx + b, where slope = m, and b is the y-intercept.
So the slope is -2/7
The slope of the perpendicular is a number that when multiplied by -2/7 you get -1.
Call it n, then n*(-2/27) = -1
Solve for n. What do you get?

Answer 2

yeah i got it lol

Answer 3

Now that you know the concept, here's how you do it quickly.

Answer 4

If two numbers are reciprocals, and you know the first one, to get the second one, write the first one as a fraction and flip it.

Answer 5

Since in this case the numbers are negativce reciprocals, then flip the fraction and change the sign.
If one line has slope -5/6, a perpendicular has slope 6/5 (flip the fraction and change the sign)

Answer 6

i get it thx

Answer 7

Great, wlcm